News of the Week

In science news around the world this week, China's government has acknowledged the existence of places where environmental hazards have contributed to elevated cancer rates, an Institute of Medicine report gave the President's Emergency Plan for AIDS Relief high marks, and more.

About The Cover

COVER The rock pigeon (Columba livia) exhibits spectacular variation among more than 350 different domestic breeds. The adult male Old Dutch capuchine shown here is one of many breeds with a crest of reversed feathers on its head and neck. See page 1063 for a description of the genetic origins of the head crest and the relationships among breeds. For the story behind the cover, go to http://scim.ag/cov_6123. Photo: Sydney Stringham